A decay series Often the product of one radioactive decay is also radioactive – this produces a radioactive decay series Try and work out the ??????s.

Slides:



Advertisements
Similar presentations
3.125%.
Advertisements

Half-Life and Radioisotope Dating
Using the half – lives of radioactive elements. In this presentation we will learn: 1.That there is an isotope of carbon that is useful for dating materials.
1 Radioactivity and Half-Life. 2 Radioactivity An unstable atomic nucleus emits a form of radiation (alpha, beta, or gamma) to become stable. In other.
. DVD 1 Bmk 5, Half life and Questions Notes for teachers using this resource… This set of slides is part of a series Half Life and includes: 1.
Chapter 4.1. Half-Life Original Sample One half-life Two half-lives Three half-lives Contains a certain One-half of the One-fourth of One-eight of the.
Half Life Calculation of Radioactive Decay Atomic Physics.
Honors Precalculus: Do Now Solve for x. 4 2x – 1 = 3 x – 3 You deposit $7550 in an account that pays 7.25% interest compounded continuously. How long will.
Radiometric Dating.
Radioactive Dating The principle:
It’s better to have a half-life than no life!
Radioactivity half-life half longer unique has a t½ = 3 min 50% 25%
Half life Not the video game
EARTH’S HISTORY RADIOMETRIC DATING
Section 1: What is Radioactivity?
A is for Atom A is for Atom.
Radioactivity.
EARTH’S HISTORY RADIOMETRIC DATING
Absolute Dating Radioactive Dating.
Measuring the speed of radioactive decay
Chemistry Do Now Directions: Take out your Do Now sheet and begin.  
Half – Life Problems.
1. What are the three types of decay we walked about yesterday?
Atomic Theory Unit Half-Life.
Radioactive Dating Calculating the age of a sample based
Half Lives in a Half Hour
Review: Types of decay 1. Alpha.
100% 50% 25% Each half life reduces the mass of the sample by half. Calculate the half life of a substance if 12.5 % of it remains after 90 years?
Half Life & Radioactive Decay
Half-Life 7.2.
Half-life.
Uranium has an atomic number greater than
Radiation and Half-Life
Absolute Dating.
Radioactivity, Half-life, and Nuclear Reactions
Geologic Time and Earth History Part 2 – Absolute Age
Nuclear Decay Series & Isotopic Half-Lifes
Rate of Radioactive Decay
7.2 What is Half Life? Half Life is the time required for half of the radioactive sample to decay. (c) McGraw Hill Ryerson 2007.
Nuclear Radiation What happens when an element undergoes radioactive decay? After radioactive decay, the element changes into a different isotope of the.
Measuring the speed of radioactive decay
Absolute Dating.
Absolute Dating.
Radioactive Decay Marie Curie and her husband Pierre discovered polonium and radium in The simplest decay form is that of a gamma ray, which represents.
Time it takes for ½ of a radioisotope to decay
Nuclear Decay Half-Life Practice.
Nuclear Decay Series & Isotopic Half-Lifes
Learning Objectives: What is half-life
Absolute Dating.
Warm up: The half life of a particular element is 10 days. Answer the following questions using that information. How many days will have passed after.
The half-life of a radioactive element is the time it takes for half of its atoms to decay into something else If you have 100 grams of a substance and.
Half-Life.
Rate of Radioactive Decay
Half Life.
Radioactive Decay.
Absolute Dating.
How can we explain absolute dating?
Half-Life HALF-LIFE is the time that it takes for 1/2 a sample to decompose. The rate of a nuclear transformation depends only on the “reactant” concentration.
Radioactive Dating.
These stone tools from the archaeological site in Cactus Hill, Virginia, are at least 15,000 years old. Scientists estimated the age of the site based.
2.2 Half-life Objective 1:i
Aim: What is a half life of an element?
Absolute Dating.
Section 1: What is Radioactivity?
7.2 Half-Life.
Half Life and Radioactive Decay
Nuclear Transformations
Half Life To understand that the time it takes for half of the unstable atoms to decay is called the half life.
Presentation transcript:

A decay series Often the product of one radioactive decay is also radioactive – this produces a radioactive decay series Try and work out the ??????s

Decay Series A decay series occurs when one radioactive isotope decays to another radioactive isotope, which decays to another, and so on. This allows the creation of nuclei that otherwise would not exist in nature.

1 mole would have a mass of 238 grams 1 mole would have a mass of 238 grams.  1 mole contains 6 x 10^23 atoms so the mass of one atom U-238 would be 238/(6x10^23) = 39.7 x 10^-23 gram or more properly 3.97 x 10^-22 gram 

Half-Life The “half-life” (h) is the time it takes for half the atoms of a radioactive substance to decay. For example, suppose we had 20,000 atoms of a radioactive substance. If the half-life is 1 hour, how many atoms of that substance would be left after: Time #atoms remaining % of atoms remaining 1 hour ? 10,000 (50%) 2 hours ? 5,000 (25%) 3 hours ? 2,500 (12.5%)

Decay curves Example for; No = 100 nuclei T1/2 = 5 days Nuclei remaining as a function of time 100 80 60 40 20 5 10 15 Time (days)

See PhET alpha-decay applet

. Carbon Dating

How old is a piece of wood 3 half lives of C-14 since the time the tree died? Half life of C14 = 5730 years . 1 half life 1 half life 1 half life ? ? ? ? ? ?

See PhET radioactive-dating-game applet

After a tree dies, it no longer absorbs C-14 from the atmosphere. When the tree dies, the C-14 in it starts to decay. The half life of the isotope C -14 is 5700 years. A sample of a fossil tree has 1000 nuclei of C-14. How long ago did the tree die? A 5.7 years old B 4800 years old C 6800 years old D D not enough information Answer

After a tree dies, it no longer absorbs C-14 from the atmosphere. When the tree dies, the C-14 in it starts to decay. The half life of the isotope C -14 is 5700 years. A sample of fossil tree gives a radioactivity count of 625 counts per second. The moment the tree died its radioactivity count was 10000 counts per second. How long ago did the tree die? A 11400 years old B 22900 years old Answer C 900 years old D not enough information

After a tree dies, it no longer absorbs C-14 from the atmosphere. When the tree dies, the C-14 in it starts to decay. The half life of the isotope C -14 is 5700 years. A 5g sample of fossil tree gives a radioactivity count of 50 counts per second. The moment the tree died its radioactivity count was 1000 counts per second per gram. How long ago did the tree die? A 17000 years old B 23000 years old 35000 years old Answer C D not enough information